"He's going to go back to Colorado to be closer to home," Auburn coach Gus Malzahn said in May. "Wish him nothing but the best. Great kid, very good person."

Callahan, who arrived at Auburn as part of the Tigers' highly-touted offensive line class of 2012, finished spring practice behind Shon Coleman, Patrick Miller, Avery Young, Robert Leff and Will Adams at practice, and Auburn added Ole Miss transfer Austin Golson in May, in addition to 2014 signee Braden Smith, who has opened spring practice by working at tackle.